Re: Tracing causes segfault when catching exception

[Daniel Diaz]

Hi Jasper

I could reproduce the bug.
I'm investigating where does it come from. It seems -O causes a bad use 
of ebx which is normally reserved for gprolog.
A workaround consists in no using ebx. Configure with:

./configure --disable-regs

It seems OK for me (with gcc 4.1.2)

If not OK can you try with:

./configure --disable-regs --with-c-flags=-O2

Thanks

> Quick follow-up -- I just tried this again, having recompiled gprolog 
> without any C flags, and now the bug does not occur. The following trace 
> output is produced, which is more or less what I would expect...
>
> | ?- on_exception(B, A is text, fail).
>       1    1  Call: on_exception(_16,_17 is text,fail) ?
>       2    2  Call: '$catch'(_17 is text,_16,fail,on_exception,3,true) ?
>       3    3  Call: _17 is text ?
>       3    3  Exception: _17 is text ?
>       2    2  Fail: '$catch'(_17 is text,_16,fail,on_exception,3,true) ?
>       1    1  Fail: on_exception(_16,_17 is text,fail) ?
>
> no
> {trace}
> | ?-
>
> ...so it is something to do with compiler optimization.
>     --Jasper
>
> Jasper Taylor wrote:
> > Hi Daniel,
> >
> > This happens on Ubuntu Linux 8.04 (files are in Windows partition but 
> > that shouldn't matter) on a Macbook with a Core 2 Duo processor. 
> > Because my main problem depends on the flags used to compile gprolog, 
> > I rebuilt it with -O and -O3, and got the problem both times.
> >
> > Here's the gcc version info:
> >
> > $ gcc -v
> > Using built-in specs.
> > Target: i486-linux-gnu
> > Configured with: ../src/configure -v 
> > --enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr 
> > --enable-shared --with-system-zlib --libexecdir=/usr/lib 
> > --without-included-gettext --enable-threads=posix --enable-nls 
> > --with-gxx-include-dir=/usr/include/c++/4.2 --program-suffix=-4.2 
> > --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc 
> > --enable-mpfr --enable-targets=all --enable-checking=release 
> > --build=i486-linux-gnu --host=i486-linux-gnu --target=i486-linux-gnu
> > Thread model: posix
> > gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu7)
> >
> > Hope this helps. Let me know if you'd like me to test it in Windows or 
> > MacOS.
> >
> >     --Jasper
> >
> > Daniel Diaz wrote:
> > > Hi Jasper,
> > >
> > > can you give me more information about your architecture (OS, 
> > > compiler, flags used to compiler gprolog,...). BTW it iseems you are 
> > > under win XP, you should avoid spaces in path names (e.g. Program 
> > > Files) because gprolog does not handle those spaces correctly...
> >
> >
> > _______________________________________________
> > Bug-prolog mailing list
> > address@hidden
> > http://lists.gnu.org/mailman/listinfo/bug-prolog
>
>
>
> _______________________________________________
> Bug-prolog mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/bug-prolog


--
Ce message a ete verifie par MailScanner
pour des virus ou des polluriels et rien de
suspect n'a ete trouve.